Heat pump system

Abstract

To provide a heat pump system capable of reducing power consumption of an electric heat pump with a simple constitution in a case when cold output of an adsorption-type heat pump is insufficient.SOLUTION: In a heat pump system including: an adsorption-type heat pump; an electric heat pump; and a control device, the control device controls the adsorption-type heat pump while switching a first mode for driving the adsorption-type heat pump, a second mode for driving the electric heat pump, and a third mode for driving the adsorption-type heat pump and the electric heat pump, and controls to supply cold heat to a condenser of the electric heat pump from an adsorption mechanism in the second mode.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a heat pump system.

Background Art

[0002] As an adsorption heat pump, Patent Document 1 describes a configuration including an evaporator, an adsorber, and a heat storage reactor. The heat storage reactor stores heat and releases heat to the adsorber that is greater than the latent heat of vaporization of the heat medium, and regenerates the adsorber by applying heat above the regeneration temperature.

[0003] An electric heat pump is also known. A hybrid system in which an adsorption heat pump and an electric heat pump are installed side by side is also known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a conventional hybrid system, as shown in FIG. 11, the evaporator of an adsorption heat pump (Adsorption. Heat Pump: AHP) and the evaporator of an electric heat pump (Electric Heat Pump: EHP) are connected in series in a cold water circulation system.

[0006] In addition, in an adsorption heat pump, there is a problem that the output at low temperatures decreases significantly. Therefore, in actual use, an electric heat pump is used as a backup for the adsorption heat pump. However, there is a problem that the cost simply increases.

[0007] This invention was made in view of the above circumstances, and aims to reduce the power consumption of an electric heat pump with a simple configuration when the cooling output of an adsorption heat pump is insufficient. [Means for solving the problem]

[0008] The heat pump system according to the present invention is a heat pump system comprising an adsorption type heat pump, an electric heat pump, and a control device, The aforementioned adsorption-type heat pump is Evaporator and, An adsorption mechanism comprising a plurality of adsorbents configured to adsorb the fluid evaporated in the evaporator, A condenser configured to condense the fluid desorbed from the adsorption mechanism, The system comprises a load to which the cold energy generated in the evaporator is supplied, The aforementioned electric heat pump is A compressor configured to produce compressed refrigerant, A condenser configured to condense compressed refrigerant and supply it to an expansion valve, An expansion valve configured to expand the condensed refrigerant, The system comprises an evaporator configured to generate cold energy from an expanded refrigerant and supply it to the load, and to supply the refrigerant to the compressor, The control device is controlled to operate by switching between a first mode for driving the adsorption heat pump, a second mode for driving the electric heat pump, and a third mode for driving both the adsorption heat pump and the electric heat pump. In the second mode, the system is controlled to supply cold air from the adsorption mechanism to the condenser of the electric heat pump.

[0009] In the heat pump system according to the present invention, the control device controls the system to switch between operating in one of three modes: a first mode for driving the adsorption heat pump, a second mode for driving the electric heat pump, and a third mode for driving both the adsorption heat pump and the electric heat pump. In the second mode, the system controls the system to supply cooling energy from the adsorption mechanism to the condenser of the electric heat pump. In this way, with a simple configuration, the power consumption of the electric heat pump can be reduced when the cooling output of the adsorption heat pump is insufficient.

[0010] Furthermore, the control device according to the present invention compares the output of the adsorption heat pump with the required cooling output. If the output of the adsorption heat pump is greater, it switches to the first mode. If the output of the adsorption heat pump is less than or equal to the required cooling output, it determines the power consumption of the second mode and the power consumption of the third mode and switches to the mode with the lower power consumption.

[0011] Furthermore, the evaporator of the adsorption-type heat pump according to the present invention can be used as the evaporator of the electric heat pump.

[0012] Furthermore, the condenser of the electric heat pump according to the present invention is configured to use a second evaporator that evaporates the fluid using a compressed refrigerant, and the condenser of the adsorption heat pump may be configured to further condense the fluid evaporated in the second evaporator.

[0013] Furthermore, the second evaporator according to the present invention is a plurality of evaporators that are connected in series with the compressor and evaporate the fluid using the compressed refrigerant, wherein the evaporator closer to the compressor is configured to supply the evaporated fluid to the condenser, and the evaporator further away from the compressor is configured to supply the evaporated fluid to the adsorption mechanism.

[0014] Further, the above fluid can be water, and the refrigerant can be a fluorocarbon gas.

Advantages of the Invention

[0015] According to the present invention, there is provided a heat pump system that can reduce the power consumption of an electric heat pump when the cooling and heating output of an adsorption heat pump is insufficient with a simple configuration.

Brief Description of the Drawings

[0016] [Figure 1] It is a schematic diagram showing a configuration example of a heat pump system according to a first embodiment of the present invention. [Figure 2] It is a diagram for explaining the operation of the high-efficiency mode in the heat pump system according to the first embodiment of the present invention. [Figure 3] It is a contour diagram showing a scatter diagram of the equilibrium adsorption amount of the adsorbent with respect to the adsorber temperature and the exhaust heat temperature. [Figure 4] It is a graph showing the relationship between the actual power consumption of the compressor in an electric heat pump, the ambient temperature, and the cooling and heating temperature. [Figure 5] It is a diagram for explaining the operation of the AHP single mode in the heat pump system according to the first embodiment of the present invention. [Figure 6] It is a diagram for explaining the operation of the parallel drive mode in the heat pump system according to the first embodiment of the present invention. [Figure 7] It is a diagram for explaining the operation of the EHP single mode in the heat pump system according to the first embodiment of the present invention. [Figure 8] It is a contour diagram showing a scatter diagram of the equilibrium adsorption amount of the adsorbent with respect to the adsorber temperature and the exhaust heat temperature. [Figure 9] It is a flowchart showing the mode switching process by the control device. [Figure 10] It is a diagram for explaining the operation of the high-efficiency mode in the heat pump system according to the second embodiment of the present invention. [Figure 11] It is a schematic diagram showing the configuration of a heat pump system in the prior art. [Modes for carrying out the invention]

[0017] Embodiments of the present invention will be described in detail below with reference to the drawings.

[0018] (Summary of Embodiments of the Invention) Adsorption heat pumps can be excellent heat pumps with very low power consumption when there is sufficient waste heat and the ambient temperature is below a threshold. However, they have the challenge of significantly reduced output at low temperatures when the waste heat temperature drops or when the ambient temperature exceeds the adsorption threshold. For this reason, in practical use, electric heat pumps are often installed as backups to adsorption heat pumps, which increases costs.

[0019] This is due to the following reasons: The output of an adsorption heat pump is determined by the adsorbent temperature, the desired cooling temperature, and the properties of the adsorbent. However, regardless of the type of adsorbent used, performance deteriorates as the cooling temperature decreases and the adsorbent temperature increases, because the adsorption capacity decreases.

[0020] In the case of commonly used silica gel, it is known that its cooling capacity drops significantly when generating temperatures below 10°C or when the ambient temperature exceeds 35°C. For this reason, electric heat pumps are often installed as backups for adsorption heat pumps, which simply increases costs.

[0021] Therefore, in this embodiment of the present invention, the adsorption heat pump and the electric heat pump are integrated, thereby commonizing the condenser, evaporator, and heat transport system piping. Furthermore, when the output of the adsorption heat pump is insufficient to meet the required cooling output, the output of the adsorption heat pump is used to assist the electric heat pump, thereby significantly improving the COP (Coefficient of Performance) of the electric heat pump.

[0022] Specifically, the heat pump system includes both an adsorption heat pump and an electric heat pump. The adsorption heat pump provides cooling to the electric heat pump's condenser, or the adsorption heat pump provides cooling at ambient temperature to the electric heat pump's condenser.

[0023] More specifically, by integrating the evaporator of the electric heat pump with the evaporator of the adsorption heat pump, it is possible to transfer the cooling energy of the adsorption heat pump to the condenser of the electric heat pump, or to transfer the cooling energy of the ambient temperature generated by the adsorption heat pump to the condenser of the electric heat pump.

[0024] Furthermore, the condenser of the electric heat pump is integrated with the second evaporator of the adsorption heat pump, and the heat source that should be discarded by the electric heat pump is discharged through piping within the adsorption heat pump to the condenser of the adsorption heat pump.

[0025] Furthermore, in cases where the output of the adsorption heat pump is less than the required cooling output due to reasons such as a high ambient temperature or a low exhaust heat temperature, the piping connection to the adsorbent can be switched to allow water vapor to be adsorbed from the second evaporator to the adsorbent.

[0026] (Configuration of the heat pump system according to the first embodiment) A heat pump system according to the first embodiment of the present invention will be described with reference to Figures 1 to 9. In this embodiment, a heat pump system using silica gel as the physical adsorbent of the adsorbent and water vapor (water) as the fluid supplied to the adsorbent, and an electric heat pump using Freon gas as the refrigerant will be described in detail as an example.

[0027] As shown in Figure 1, the heat pump system 100 of this embodiment is an adsorption type heat pump comprising an adsorption mechanism 10 consisting of a first adsorbent 11 and a second adsorbent 12 configured to adsorb a fluid (water vapor), a first evaporator 21, a condenser 30 that condenses the fluid discharged from the first adsorbent 11 and the second adsorbent 12, and a load 40.

[0028] The first evaporator 21 vaporizes water and is connected to the first adsorber 11 and the second adsorber 12, respectively, so that it can supply water vapor, which is the fluid produced by the vaporization. Specifically, one end of a flow pipe 75 having a valve V1, which is a flow control valve, is connected to the first evaporator 21.

[0029] As described above, the first evaporator 21 absorbs heat of vaporization by vaporizing the fluid, thereby generating cooling energy equivalent to the heat of vaporization of water vapor. Since the first evaporator 21 is thermally connected to a load 40, such as an air conditioner outdoor unit, which is an example of a cooling demand, via heat exchange pipes 85 and 86 through which circulating water flows, effective utilization of the cooling energy is possible.

[0030] The first adsorbent 11 is configured to receive water vapor from the first evaporator 21, adsorb and retain the water vapor, and desorb the adsorbed water vapor and release it to the condenser 30. Specifically, the first adsorbent 11 is connected to one end of a flow pipe 74 having a valve V5 and to the other end of a flow pipe 77 having a valve V7.

[0031] The second adsorbent 12 is configured to receive water vapor from the first evaporator 21, adsorb and retain the water vapor, and desorb and release the adsorbed water vapor. Specifically, the second adsorbent 12 is connected to one end of a flow pipe 73 having a valve V4 and to one end of a flow pipe 76 having a valve V6.

[0032] The condenser 30 is connected to allow the supply of water vapor from the first adsorber 11 and the second adsorber 12, and condenses the water vapor supplied from the first adsorber 11 and the second adsorber 12. Specifically, the condenser 30 is connected to one end of a flow pipe 76 having a valve V6 and to the other end of a flow pipe 77 having a valve V7.

[0033] Furthermore, the condenser 30 is connected to the second evaporator 22 via a flow pipe 71 having a valve V3, and condenses the water vapor supplied from the second evaporator 22.

[0034] Furthermore, the condenser 30 is connected to the first evaporator 21 and the second evaporator 22 by a flow piping (not shown) that includes a pump. The water condensed in the condenser 30 is supplied to the first evaporator 21 and the second evaporator 22 through the flow piping.

[0035] As shown in Figure 1 above, the heat pump system 100 is an electric heat pump comprising a compressor 50 configured to generate compressed refrigerant, an expansion valve 60 configured to expand the refrigerant, and a second evaporator 22.

[0036] The second evaporator 22 functions as a condenser configured to condense the compressed refrigerant and supply it to the expansion valve 60. The second evaporator 22 also uses the compressed refrigerant to evaporate the fluid and supply it to the condenser 30. Specifically, one end of a flow pipe 71 having a valve V3 is connected to the second evaporator 22.

[0037] The second evaporator 22 is connected to the compressor 50 and the expansion valve 60, respectively, so that it can be supplied with fluorocarbon gas, which is a refrigerant. Specifically, one end of the flow pipes 81 and 82 is connected to the second evaporator 22.

[0038] Furthermore, the first evaporator 21 is also used as an evaporator for an electric heat pump, which is configured to generate cooling from the expanded refrigerant and supply the refrigerant to the compressor 50.

[0039] The first evaporator 21 is connected to the compressor 50 and the expansion valve 60, respectively, so that it can supply fluorocarbon gas, which is a refrigerant. Specifically, one end of the flow pipes 83 and 84 is connected to the first evaporator 21.

[0040] The control device 90 is a control means responsible for the overall control of the heat pump system 100. It is electrically connected to valves V1 to V7, compressor 50, load 40, and external heat source, and is configured to control the utilization of cooling energy by controlling the valves, heat source, and heat exchange.

[0041] Specifically, the control device 90 is connected to an ambient temperature sensor 92 for detecting ambient temperature, an exhaust heat temperature sensor 94 for detecting exhaust heat temperature, and a load-side sensor 96 for detecting load-side information including the required cooling output, the room temperature on the load side, and the chilled water temperature of the circulating water. Based on the ambient temperature, exhaust heat temperature, required cooling output, the room temperature on the load side, and the chilled water temperature of the circulating water, the control device 90 controls the system to switch between AHP standalone mode, which drives the adsorption heat pump alone; high-efficiency mode, which drives the electric heat pump alone with high efficiency; parallel drive mode, which drives the adsorption heat pump and the electric heat pump in parallel; and EHP standalone mode, which drives the electric heat pump alone. Note that AHP standalone mode is an example of the first mode, high-efficiency mode is an example of the second mode, and parallel drive mode is an example of the third mode.

[0042] Here's a description of each mode.

[0043] In high-efficiency mode, as shown in Figure 2, the system is controlled to supply cooling energy from the adsorption mechanism 10 to the second evaporator 22, which functions as a condenser for an electric heat pump.

[0044] Figure 2 shows the valve operation in high-efficiency mode, with dotted valves indicating the open state and white valves indicating the closed state. The same applies to Figures 5, 6, 7, and 10. In the example in Figure 2, the first adsorbent 11 is an adsorbent that is regenerated using waste heat, and the second adsorbent 12 is an adsorbent that is cooled to ambient temperature.

[0045] Specifically, when the compressor 50 is driven to generate cooling as an electric heat pump, valves V2 and V4 are opened, and steam is supplied from the second evaporator 22 to the second adsorber 12 via the flow pipes 71, 72, and 73, where the adsorption operation of steam takes place. As a result, cooling is supplied from the adsorption heat pump to the second evaporator 22, which functions as a condenser for the electric heat pump.

[0046] Furthermore, with valve V7 open, the water vapor desorbed from the first adsorber 11 is supplied to the condenser 30 via the flow piping 77, and the water vapor condensation operation takes place in the condenser 30.

[0047] Then, the first adsorbent 11 and the second adsorbent 12 are alternately swapped and driven like a normal adsorption heat pipe. When the first adsorbent 11 or the second adsorbent 12, cooled to ambient temperature, is connected to the second evaporator 22 via the flow piping 73 or 74 and the flow piping 71, 72, the second evaporator 22 is cooled, and the second evaporator 22, which functions as a condenser for the electric heat pump, is cooled to the cooling temperature of the adsorption heat pump, thereby reducing the power consumption of the electric heat pump's compressor 50.

[0048] To demonstrate the efficiency advantages in the high-efficiency mode, Figures 3(A) and (B) show scatter plots of equilibrium adsorption amount against adsorbent temperature (dependent on ambient temperature) and waste heat temperature for an adsorbent using RD silica gel, for two conditions: cold generation temperature of 10°C and 20°C. When the ambient temperature rises or the waste heat temperature decreases, at a cold generation temperature of 10°C, there is a large region where the adsorption amount is 0 or less, but as the cold generation temperature rises to 20°C, the region in which adsorption amount can be obtained expands.

[0049] For example, when the exhaust heat temperature is 80°C and the ambient temperature is 40°C, at a cooling temperature of 10°C, the output of the adsorption heat pump becomes 0, making air conditioning with the adsorption heat pump impossible. In this case, if we consider switching to a mode where the condensation heat of the electric heat pump is cooled, for example, at a cooling temperature of 20°C, the adsorption amount becomes 0.07, and sufficient output can be obtained. Let's consider the effect of applying this cooling heat to the condenser of the electric heat pump.

[0050] Figure 4 shows the relationship between the actual compressor power consumption, ambient temperature, and cooling temperature in an electric heat pump. If the ambient temperature in an electric heat pump can be lowered by utilizing the cooling of an adsorption heat pump, and if the ambient temperature can be lowered by about 20°C from 40°C under the conditions mentioned above, it becomes possible to significantly reduce the compressor power consumption Qcomp. For example, lowering the ambient temperature by about 20°C from 40°C can reduce the compressor power consumption Qcomp by 33%.

[0051] In this case, the cooling output calculated using an electric heat map, assuming ideal operation, is the cooling output QAHP from the adsorption heat pump minus the compressor power consumption Qcomp. The power consumption Qcon of an adsorption heat pump equipped with a water-spray condenser is approximately 1 / 30 of the cooling output QAHP. When considering a large steam-transport type adsorption heat pump, excluding the power of auxiliary equipment such as air valves for driving the valves, the power consumption is predominantly for the condenser's water spray pump and fan power, requiring approximately 1 / 30 of the cooling amount in power. Here, assuming that it is 1 / 30, the calculation is as follows: JPEG0007851760000001.jpg22109 Therefore, as shown in Figure 7, when operating with the same capacity in EHP-only mode (a mode used when exhaust heat cannot be supplied at all to meet the cooling demand), JPEG0007851760000002.jpg24102 Therefore, the improvement is significant even when considering the power COP.

[0052] Next, the AHP standalone mode will be described. This AHP standalone mode is used when sufficient waste heat is available. In AHP standalone mode, as shown in Figure 5, the compressor 50 is not driven, valves V1 and V4 are opened, and steam is supplied from the first evaporator 21 to the second adsorber 12 via the flow pipes 72, 73, and 75, where the steam adsorption operation takes place. Also, valve V7 is opened, and the steam desorbed from the first adsorber 11 is supplied to the condenser 30 via the flow pipe 77, where the steam condensation operation takes place.

[0053] Then, the first adsorbent 11 and the second adsorbent 12 are alternately swapped to perform the adsorption and detachment operations.

[0054] Using the assumptions made so far, if we calculate the power COP in the same way, JPEG0007851760000003.jpg2577 This is the result.

[0055] In parallel drive mode, as shown in Figure 6, when the compressor 50 is driven to generate cooling as an electric heat pump, valve V3 is opened, and steam is supplied from the second evaporator 22, which functions as a condenser for the electric heat pump, to the condenser 30 via the flow piping 71, where the steam condenses. Also, with valves V1 and V4 open, steam is supplied from the first evaporator 21 to the second adsorber 12 via the flow piping 72, 73, and 75, where the steam adsorption operation takes place.

[0056] Furthermore, with valve V7 open, the water vapor desorbed from the first adsorber 11 is supplied to the condenser 30 via the flow piping 77, and the water vapor condensation operation takes place in the condenser 30.

[0057] Then, the first adsorbent 11 and the second adsorbent 12 are alternately swapped and driven as a normal adsorption-type heat pipe to supply cooling and heating.

[0058] The parallel drive mode is used in situations where there is a high demand for cooling, sufficient waste heat, and the output of the electric heat pump is still required even when the adsorption heat pump is operating at its rated capacity. In this mode, the power COP is the average value according to the operating ratio of each component.

[0059] When sufficient heat is available, in the parallel drive mode operation shown in Figure 6, after adsorption from the first evaporator 21 is completed in the adsorption heat pump, it is possible to switch to the operation mode shown in Figure 2 and then perform adsorption from the second evaporator 22, thereby achieving both high-efficiency operation of the electric heat pump and operation of the adsorption heat pump simultaneously.

[0060] Next, the EHP standalone mode will be described. In the EHP standalone mode, as shown in Figure 5, the compressor 50 is driven to generate cooling as an electric heat pump. At this time, the valve V3 is opened, and steam is supplied from the second evaporator 22, which functions as a condenser for the electric heat pump, to the condenser 30 via the flow piping 71, where the steam condenses.

[0061] Next, we will explain the efficiency of each mode. As an example, when the ambient temperature is 30°C and the waste heat temperature is 85°C, the difference in adsorption amount at a cooling temperature of 10°C is approximately 0.05 g / g, as shown in Figure 8(A). On the other hand, the difference in adsorption amount at a cooling temperature of 20°C is 0.15 g / g, as shown in Figure 8(B). Therefore, we consider the case where, as an adsorption-type heat pump, adsorption reaches 0.05 g / g at a cooling temperature of 10°C, and then, as assistance to the second evaporator 22 which functions as a condenser for an electric heat pump, adsorption reaches 0.15 g / g at a cooling temperature of 20°C.

[0062] Furthermore, when an adsorption heat pump operates alone and adsorbs down to 0.05 g / g, the amount of heat required is the sum of the sensible heat and latent heat of the adsorbent. Assuming the thermal COP at this time is 0.5, the thermal efficiency when using an electric heat pump in combination should take into account the increase in latent heat from 0.05 g / g to 0.15 g / g.

[0063] In this case, since the power consumption is the same as in the high-efficiency mode shown in Figure 2, the power COP and thermal COP are as follows.

[0064] In AHP standalone mode, the power COP is 30 and the thermal COP is 0.5. In high-efficiency mode, the power COP is 3.28 and the thermal COP is 0.7. In EHP standalone mode, the power COP is 1.53.

[0065] In high-efficiency mode, a higher power COP is obtained compared to operating in EHP-only mode. However, since the power COP is lower compared to AHP-only mode, mode selection must be made considering the balance between cooling demand and waste heat. In addition, in high-efficiency mode, a large difference in adsorption amount can be obtained for a single adsorption / desorption switch (3 times in this calculation example), resulting in a high thermal COP. Therefore, a notable feature is that the heat consumption per unit of cooling is significantly reduced.

[0066] Next, the mode switching process performed by the control device 90 will be explained in detail.

[0067] First, the difference in adsorption amount relative to the operating temperature of the adsorption heat pump (cooling temperature, ambient temperature, and waste heat temperature) is represented as a three-dimensional map showing the adsorption isotherms of the adsorbent material in the adsorption mechanism 10, as shown in Figure 3 above. Note that Figure 3 is shown in two dimensions for space limitations.

[0068] The ambient temperature and waste heat temperature are determined using values ​​obtained by the ambient temperature sensor 92 and the waste heat temperature sensor 94. Here, the cooling generation temperature is determined from the required cooling output obtained by the load-side sensor 96, the room temperature on the load side, and the chilled water temperature of the circulating water. The adsorption amount difference Δq can be determined from the map described above.

[0069] Furthermore, the output of an adsorption heat pump is determined by the adsorption amount difference Δq, the latent heat of vaporization (a known value), and the adsorption cycle time. The cycle time, like the adsorption amount, is a value that varies depending on the operating temperature of the adsorption heat pump and the design of the adsorber, so it is assumed that this value has been acquired in advance using a 3D map.

[0070] If the output of the requested adsorption heat pump is greater than the required cooling output, the system switches to AHP (Automatic Heat Pump) standalone mode to supply cooling. This is the most efficient operating mode.

[0071] Next, if the output of the adsorption heat pump is less than the required cooling output, the system switches to the mode with lower power consumption among the parallel drive mode and the high-efficiency mode to supply cooling.

[0072] The power consumption of an electric heat pump in parallel drive mode is calculated as follows: First, the power consumption of the electric heat pump is calculated using a map determined from the required cooling output and ambient temperature. Alternatively, the output of the electric heat pump = required cooling output - the output of the adsorption heat pump, and the power consumption of the electric heat pump can be determined from the map of the electric heat pump's output and ambient temperature.

[0073] The power consumption in high-efficiency mode is calculated as follows. First, the output of the adsorption heat pump is determined from the operating temperature. For this high-efficiency mode to be valid, the output of the adsorption heat pump must be greater than the required cooling output and the estimated power consumption of the compressor 50. From this, the power consumption of the compressor 50 is determined using the output of the adsorption heat pump determined by the operating temperature as described above, and the cooling temperature of the adsorption heat pump obtained from the map. The operating condition that minimizes power consumption among the valid operating conditions is then determined, and the power consumption at that time is calculated.

[0074] The power consumption of the parallel drive mode and the power consumption of the high-efficiency mode are compared, and the system switches to the mode with lower power consumption to supply cooling.

[0075] Furthermore, if the output of the adsorption heat pump is below the threshold, there is a concern that exhaust heat will be wasted. Therefore, if it is expected that the output of the adsorption heat pump will fall below the threshold, the output of the adsorption heat pump will be stopped, and the system will switch to EHP (electric heat pump) alone mode to supply cooling.

[0076] (Heat pump system operation) Next, the operation of supplying cooling to the load 40 in the heat pump system 100 of this embodiment will be described.

[0077] The control device 90 periodically performs the mode switching process shown in Figure 9.

[0078] First, in step S100, the control device 90 acquires load-side information including the ambient temperature detected by the ambient temperature sensor 92, the exhaust heat temperature detected by the exhaust heat temperature sensor 94, and the requested cooling output detected by the load-side sensor 96, the room temperature on the load side, and the chilled water temperature of the circulating water.

[0079] In step S102, the control device 90 calculates the output of the adsorption heat pump.

[0080] In step S104, the control device 90 compares the output of the adsorption heat pump with the required cooling output and determines whether the output of the adsorption heat pump is greater than or equal to the required cooling output. If the output of the adsorption heat pump is greater than the required cooling output, the process proceeds to step S106. On the other hand, if the output of the adsorption heat pump is less than or equal to the required cooling output, the process proceeds to step S108.

[0081] In step S106, the control device 90 switches to AHP standalone mode and performs operation control.

[0082] In step S108, the control device 90 determines whether the output of the adsorption heat pump is less than a threshold. If the output of the adsorption heat pump is less than the threshold, the process proceeds to step S110. On the other hand, if the output of the adsorption heat pump is equal to or greater than the threshold, the process proceeds to step S112.

[0083] In step S110, the control device 90 switches to EHP standalone mode and performs operation control.

[0084] In step S112, the control device 90 calculates the power consumption in parallel drive mode and the power consumption in high-efficiency mode.

[0085] In step S114, the control device 90 determines whether the power consumption in parallel drive mode is less than the power consumption in high-efficiency mode. If the power consumption in parallel drive mode is less than the power consumption in high-efficiency mode, the process proceeds to step S116. On the other hand, if the power consumption in high-efficiency mode is less than the power consumption in parallel drive mode, the process proceeds to step S118.

[0086] In step S116, the control device 90 switches to parallel drive mode and performs operation control.

[0087] In step S118, the control device 90 switches to high-efficiency mode and performs operation control.

[0088] As described above, according to the heat pump system of the first embodiment of the present invention, the first evaporator of the adsorption heat pump is shared as the evaporator of the electric heat pump, which is configured to generate cold from an expanded refrigerant and supply the refrigerant to a compressor. When the electric heat pump generates cold, the second evaporator uses the refrigerant compressed by the compressor to evaporate the fluid and supply the refrigerant to the expansion valve. At this time, the adsorption mechanism of the adsorption heat pump adsorbs the fluid evaporated in the second evaporator. In this way, with a simple configuration, the power consumption of the electric heat pump can be reduced when the cold output of the adsorption heat pump is insufficient.

[0089] Furthermore, by supplying the cold energy generated by the adsorption heat pump, which is lower than the ambient temperature, to the second evaporator that functions as a condenser in the electric heat pump, it is possible to lower the condenser pressure. As a result, in conditions where the ambient temperature is high enough that the adsorption heat pump cannot operate in normal mode, the compressor power becomes large, but by lowering the condenser pressure, the compressor power can be significantly reduced. In addition, the efficiency of the electric heat pump can be greatly improved when the heat exhaust source is insufficient.

[0090] Furthermore, by integrating the adsorption-type heat pump and the electric heat pump, and sharing the condenser and evaporator, the indoor and outdoor unit parts for the electric heat pump are eliminated, reducing the number of parts.

[0091] Furthermore, when the outside temperature is high or the exhaust heat temperature is low, the COP of the electric heat pump can be improved by using the cooling energy of approximately 25°C generated on the adsorption heat pump side, which is difficult to use for normal cooling, to lower the condenser pressure on the electric heat pump side.

[0092] Furthermore, when there is a high demand for cooling, the efficiency of the electric heat pump can be improved by reducing the condensation heat of the electric heat pump using the cooling generated by the adsorption heat pump after the normal cooling generation of the adsorption heat pump.

[0093] Furthermore, if there is ample waste heat, operation in parallel drive mode becomes possible. After the adsorption of the cooling energy generated by the adsorption heat pump is complete, adsorption is performed to process the condensation heat of the electric heat pump, thereby reducing the power consumption of the compressor. In this case, in addition to the heat required for the AHP in standalone mode, the heat required for the condensation heat processing in the electric heat pump is also required, but since it can handle most of the sensible heat, the total amount of cooling energy generated per unit of heat is increased.

[0094] (Second Embodiment) A heat pump system according to a second embodiment of the present invention will be described with reference to Figure 10. This embodiment has a system configuration using two second evaporators. Parts that have the same configuration as in the first embodiment are denoted by the same reference numerals and their description is omitted.

[0095] As shown in Figure 10, the heat pump system 200 is an electric heat pump comprising a compressor 50, an expansion valve 60, and second evaporators 221 and 222.

[0096] The second evaporators 221 and 222 function as condensers configured to condense the compressed refrigerant and supply it to the expansion valve 60.

[0097] The second evaporator 221, which is closer to the compressor 50, is configured to supply the evaporated fluid to the condenser 30. Specifically, one end of the flow piping 71 is connected to the second evaporator 221.

[0098] Furthermore, the second evaporator 222, which is further away from the compressor 50, is configured to supply the evaporated fluid to the adsorption mechanism 10. Specifically, one end of the flow piping 78 is connected to the second evaporator 222.

[0099] The second evaporator 221 is connected to the compressor 50 and the second evaporator 222, respectively, so that it can be supplied with a fluid, which is a fluorocarbon gas. Specifically, one end of the flow pipes 81 and 85 is connected to the second evaporator 221.

[0100] The first evaporator 222 is connected to the first evaporator 221 and the expansion valve 60, respectively, so that it can be supplied with the fluid, which is fluorocarbon gas. Specifically, one end of the flow pipes 82 and 85 is connected to the second evaporator 222.

[0101] In high-efficiency mode, as shown in Figure 10, the system is controlled to supply cooling energy from the adsorption mechanism 10 to the second evaporator 222, which functions as a condenser for an electric heat pump.

[0102] In the example shown in Figure 10, the first adsorbent 11 is an adsorbent that is regenerated using waste heat, and the second adsorbent 12 is an adsorbent that is cooled to ambient temperature. Specifically, when the compressor 50 is driven to generate cooling as an electric heat pump, valves V2, V3, and V8 are opened, and steam is supplied from the second evaporator 221 to the condenser 30 via the flow piping 71, where the steam condenses. Also, steam is supplied from the second evaporator 222 to the second adsorbent 12 via the flow piping 72, 73, and 78, where the steam adsorption operation takes place.

[0103] Furthermore, with valve V7 open, the water vapor desorbed from the first adsorber 11 is supplied to the condenser 30 via the flow piping 77, and the water vapor condensation operation takes place in the condenser 30.

[0104] The first adsorbent 11 and the second adsorbent 12 are then alternately switched and driven like a normal adsorption heat pipe. When the first adsorbent 11 or the second adsorbent 12, cooled to ambient temperature, is connected to the second evaporator 222 via the flow piping 73 or 74 and the flow piping 72, the second evaporator 222 is cooled, and the second evaporator 222, which functions as a condenser for the electric heat pump, is cooled to the cooling temperature of the adsorption heat pump, thus reducing the power consumption of the electric heat pump's compressor 50.

[0105] The other components and operations of the heat pump system 200 are the same as in the first embodiment, so their explanation will be omitted. [Explanation of symbols]

[0106] 10 Adsorption mechanism 11 1st adsorber 12 Second adsorber 20 Cold generation temperature 21, 221 First evaporator 22,222 Second evaporator 30 Condenser 40 load 50 Compressors 60 Expansion valve 71~77 Distribution piping 81~84 Distribution piping 85, 86 heat exchange tube 90 Control device 92 Ambient temperature sensor 94 Exhaust Heat Temperature Sensor 96 Load-side sensor 100, 200 Heat Pump Systems V1~V8 valves

Claims

1. A heat pump system comprising an adsorption heat pump, an electric heat pump, and a control device, The aforementioned adsorption-type heat pump is Evaporator and, An adsorption mechanism comprising a plurality of adsorbents configured to adsorb the fluid evaporated in the evaporator, A condenser configured to condense the fluid desorbed from the adsorption mechanism, The system comprises a load to which the cold energy generated in the evaporator is supplied, The aforementioned electric heat pump is A compressor configured to produce compressed refrigerant, A condenser configured to condense compressed refrigerant and supply it to an expansion valve, An expansion valve configured to expand the condensed refrigerant, The system comprises an evaporator configured to generate cold energy from an expanded refrigerant and supply it to the load, and to supply the refrigerant to the compressor, The control device is controlled to operate by switching between a first mode for driving the adsorption heat pump, a second mode for driving the electric heat pump, and a third mode for driving both the adsorption heat pump and the electric heat pump. In the second mode, the adsorption mechanism is controlled to supply cold air to the condenser of the electric heat pump. The control device compares the output of the adsorption heat pump with the required cooling output, and if the output of the adsorption heat pump is greater, it switches to the first mode. A heat pump system that, when the output of the adsorption heat pump is less than or equal to the required cooling output, determines the power consumption of the second mode and the power consumption of the third mode and switches to the mode with the lower power consumption.

2. The heat pump system according to claim 1, wherein the evaporator of the adsorption type heat pump is shared as the evaporator of the electric heat pump.

3. A heat pump system comprising an adsorption heat pump, an electric heat pump, and a control device, The aforementioned adsorption-type heat pump is Evaporator and, An adsorption mechanism comprising a plurality of adsorbents configured to adsorb the fluid evaporated in the evaporator, A condenser configured to condense the fluid desorbed from the adsorption mechanism, The system comprises a load to which the cold energy generated in the evaporator is supplied, The aforementioned electric heat pump is A compressor configured to produce compressed refrigerant, A condenser configured to condense compressed refrigerant and supply it to an expansion valve, An expansion valve configured to expand the condensed refrigerant, The system comprises an evaporator configured to generate cold energy from an expanded refrigerant and supply it to the load, and to supply the refrigerant to the compressor, The control device is controlled to operate by switching between a first mode for driving the adsorption heat pump, a second mode for driving the electric heat pump, and a third mode for driving both the adsorption heat pump and the electric heat pump. In the second mode, the adsorption mechanism is controlled to supply cold air to the condenser of the electric heat pump. The condenser of the electric heat pump is configured with a second evaporator that uses compressed refrigerant to evaporate the fluid. The heat pump system wherein the condenser of the adsorption heat pump is further configured to condense the fluid evaporated in the second evaporator.

4. The second evaporator is a plurality of evaporators that are connected in series with the compressor and evaporate the fluid using the compressed refrigerant, The evaporator closer to the compressor is configured to supply the evaporated fluid to the condenser. The heat pump system according to claim 3, wherein the evaporator furthest from the compressor is configured to supply the evaporated fluid to the adsorption mechanism.

5. The heat pump system according to any one of claims 1 to 4, wherein the fluid is water and the refrigerant is a fluorocarbon gas.

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